Device for drawing in per



(No Model.)

A. BRIX. DEVICE FOR DRAWING IN PERSPECTIVE.

No. 406,083. Patented July 2, 1889..

NITED STATES PATENT OFFICE,

ALEXANDER BRIX, OF FRANKFORT-ON-THE-MAIN, PRUSSIA, GERMANY.

DEVICE FOR DRAWING IN PERSPECTIVE.

SPECIFICATION forming part of Letters Patent No. 406,083, dated July 2, 1889.

Application filed December 81, 1885. serial No. 187,293. (No model.) Patented in Germany October 12, 1883, No. 27,646, and October '7, 1885,1T0. 36,024, and in England November 10, 1885, No. 13,667.

To aZZ whom it may concern.-

Be it known that I, ALEXANDER BRIX, of Frankfort-on-the-llain, in the Kingdom of Prussia and Empire of Germany, have invented a new and useful Device for Drawing in Perspective, of which the following is a specification, reference being bad to the ac companying drawing.

This invention has been patented in Germany by Letters Patent dated October 12, 1883, No. 27,616, and additional patent dated October '7, 1885, No. 36,021 5 also in Great Britain by Letters Patent No. 13,667, dated November 10, 1885.

Said drawing represents a perspective view of the device embodying my invention.

A designates a style having a graduated upright stem Z, and movable over a drawingboard G or other fiat surface. To this style, just above its point, is jointed a rod J, which extends backward to and through a sleeve F, attached to the lower end of an upright graduated staff E, and free to turn thereon. Between said point and sleeve F said rod passes through another sleeve C, which is mounted so that it can turn in a horizontal plane on a plate R, the latter being supported by atransverse shaft X and free to slide laterally thereon. A continuous rod bent to form a long loop or frame, consisting of a vertical part B and a horizontal part B, is fastened to this plate, said upper part B thereof serving as a guide and support for a vertically-movable slide H, having a large central opening. lVithin this opening is doublyjointed a sleeve L, to allow both vertical and lateral rocking. A red J extends through this sleeve, and has at one end a sleeve D loosely jointed to it and adjustable up and down on stem Z of style A by means of a set-screw D. The said rod J, near its other end, passes through another sleeve 0, which is jointed by gimbals M to a vertical sleeve V on red E.

N designates a plate movable backward and forward on the horizontal part B of the frame aforesaid, and provided with a pencil or other drawing point K, which is pressed down against table G by a spring K. A cord S extends from slide H to plate N, passing partly around a pulley s on the way. A spring Q, bears against a stud g on said plate, tending to move the latter away from slide II and the upright part B of said frame. The rear end of said frame is supported by a transverse bar P, which is grooved to allow lateral motion of said frame. Staff E is provided with a rigid horizontal arm l V, which is bent at its outer end and inserted in a socket \V, in which it is adjustable vertically by means of a set-screw \V? This socket fits 011 the rear end of the table, and is provided with another set-screw VV for adjusting its position laterally. As this socket is the only support of said staff E, the said rod may be adjusted both vertically and sidewise with facility and convenience by means of said set-screws.

The operation of the device is as follows: The outline from which a perspective is to be drawn is secured under the style A in the re quired position with regard to the point of view, which latter is determined by adjustment of the graduated staff E. The required position of the eye or height of the horizon is fixed by screwing the sleeve V on the staff E at the appropriate point. The styleAis then carried over the outlines, and the figure represented thereby is thereupon delineated in perspective by pen or pencil K, the perspective appearing as taken from any required height, according to the adjustment of slide D, the motion of pencil or pen K being caused by the upward motion of slide H, the opposing tension of spring Q, and the lateral motion of frame B B on transverse rod X and bar P. The joints of the various rods and sleeves making up my perspectograph allow and require pen or pencil K to move with the motion of style A, but always in the exact relation existing between the outline figure and a perspective taken from. the predetermined point of view. The slide H necessarily moves upward, drawing on cord S and plate N, whenever the style A is moved toward frame B B, inasmuch as the rods J and J are arranged at an angle one to the other, their lines converging as they recede from style A toward staff E, and the lower rod J cannot move vertically at either end, while the rear end of the upper rod J is free to move upward on staff E. The reverse motion of the style A allows the spring Q to draw the plate N, pencil K, and slide H in the opposite direction.

All lateral motions of the style carry the frame laterally with it along rod X, and the pencil of course moves likewise. The oblique and curved motions of the style are transmitted to the pencil through the combination of the above agencies and modified in the transmission, as stated.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. The combination of graduated style A and staff E with laterally-movable frame B B, with plate N, movable backward and forward on said frame, drawing-point K, carried by said plate, slide 11, movable up and down on said frame, cord S, connecting said frame to said plate, spring Q, drawing said plate away from style A, rods J and J, and sleeves connecting each of said rods to said style and staif, the latter rod being also double-jointed to said slide, adjustable on said style and freely movable on said staff, substantially as set forth.v

2. In a perspectograph, a graduated staff E, which is adjustable vertically and laterally, bnt held stationary after adjustment, in combination with its adjusting devices, a graduated style A, which is freely movable, a rod J, adjustable atone end on said style and freely movable at the other on said staff, a drawing-point K, and intermediate devices connecting it to an attachment of said rod, a spring Q, drawing said point away from said style, a frame B B, connected to said rod and supporting said point, and a transverse rod on which said frame is movable laterally, substantially as set forth.

In witness whereof I have hereunto set my hand in presence of two witnesses.

ALEXANDER BRIX. 

